1. Field of the Invention
The invention relates to a power conversion technique, and more particularly, to a boost-based power factor correction power conversion apparatus and a power conversion method thereof.
2. Description of Related Art
A power conversion/supply apparatus is mainly used for converting a high-voltage and low-stability alternating current (AC) voltage provided by a power company into a low-voltage and stable direct current (DC) voltage suitable for various electronic devices. Therefore, the power conversion apparatus is widely used in electronic devices such as computers, office automation equipments, industrial control equipments, and communication equipments, etc.
The front-end of the current power conversion/supply apparatus is a power factor correction (PFC) power converter, and the back-end thereof is a pulse width modulation (PWM) power converter. Taking the power factor correction power converter as an example, the control structure thereof has mostly been employed the pulse width modulation (PWM) control chip
Conventionally, most of the current pulse width modulation control chips are built-in a “fixed” over current protection (OCP) point to perform a detection of the over current protection (OCP) in order to protect the power factor correction power converter from damaging due to the phenomena of over current (OC), and thus achieving the purpose of protecting the power factor correction power converter. However, since a receiving range of the power factor correction power converter is from 90VAC to 264VAC, and over current protection points corresponding to whether the respective over current protection (OCP) mechanisms are activated for the different input voltages of 90VAC to 264VAC are not identical. Therefore, the detection manner of the over current protection (OCP) performed by the conventional pulse width modulation control chip can not adaptively applied to different input voltages, thereby resulting in the power factor correction power converter may be damaged due to the effect of over current.